Network Working Group J. Postel
Request for Comments: 758 USC-ISI
IEN: 117 August 1979
Obsoletes RFCs: 755,
750,739, 604, 503, 433, 349
Obsoletes IENs: 93
ASSIGNED NUMBERS
This Network Working Group Request for Comments documents the currently
assigned values from several series of numbers used in network protocol
implementations. This RFC will be updated periodically, and in any case
current information can be obtained from Jon Postel. The assignment of
numbers is also handled by Jon. If you are developing a protocol or
application that will require the use of a link, socket, etc. please
contact Jon to receive a number assignment.
Jon Postel
USC - Information Sciences Institute
4676 Admiralty Way
Marina del Rey, California 90291
phone: (213) 822-1511
ARPANET mail: POSTEL@ISIB
Most of the protocols mentioned here are documented in the RFC series of
notes. The more prominent and more generally used are documented in the
Protocol Handbook [1] prepared by the Network Information Center (NIC).
In the lists that follow a bracketed number, e.g. [1], off to the right
of the page indicates a reference for the listed protocol.
Postel [Page 1]

RFC 758 August 1979
IEN 117 Assigned Numbers
Port or Socket Numbers
ASSIGNED PORT or SOCKET NUMBERS
Ports are used in the TCP [46] and sockets are used in the AHHP [1,3]
to name the ends of logical connections which carry long term
conversations. For the purpose of providing services to unknown
callers a service contact socket is defined. This list specifies the
port or socket used by the server process as its contact socket. In
the AHHP an Initial Connection Procedure ICP [1,34] is used between
the user process and the server process to make the initial contact
and establish the long term connections leaving the contact socket
free to handle other callers. In the TCP no ICP is necessary since a
port may engage in many simultaneous connections.
Socket Assignments:
General Assignments:
Decimal Octal Description
------- ----- -----------
0-63 0-77 Network Wide Standard Function
64-127 100-177 Hosts Specific Functions
128-223 200-337 Reserved for Future Use
224-255 340-377 Any Experimental Function
Postel [Page 5]